/Engine/Source/Runtime/Engine/Public/Animation/BoneSocketReference.h
There are subtle difference between this two IsValid function First one says the configuration had a valid socket as mesh index is valid Second one says the current bonecontainer doesn't contain it, meaning the current LOD is missing the joint that is required to evaluate Although the expected behavior is ambiguous, I'll still split these two, and use it accordingly
bool HasValidSetup() const